This invention relates generally to an analyzer based control system and algorithm for the use in a chemical process system. As described for example in U.S. Pat. Nos. 5,503,006, 5,425,267, 5,965,785, 5,326,482, 4,335,072, U.S. Published Patent Applications 2010/0108566 and 2012/0053861 A1, UK Patent 1,198,734, and International Patent Applications 2008/005058, 2004/044266, and 03/006581, chemical and industrial facilities utilize a variety of complex equipment, which are often subject to harsh chemical and physical conditions. As such, a number of technologies have been developed to monitor the condition, efficiency, and expected lifespan of the equipment. Such technologies include historian systems, which collect and archive data from various sources within the chemical plant. U.S. patent application Ser. No. 12/899,250 describes a number of methods of utilizing historian and other data.
Monitoring equipment typically involves a system in which a variety of process variables are measured and recorded. One such system is described in U.S. Published Patent Application 2009/0149981 A1. Such systems however often produce massive amounts of data of which only a small portion of which is usefully tracked to detect abnormal conditions and the information gleaned from those systems is of limited practical use.
In the context of corrosion prevention, three of the most useful data sets for a monitor to measure are pH, metal (especially iron) ion concentrations, and chloride ion concentrations. Ideally the monitored data is as close to real time as possible so remediation techniques for the causes of extreme concentrations can be applied before the causes effect corrosion or otherwise damage the facility. Unfortunately current monitoring technologies provide a large volume of false data so real time monitoring is usually difficult if not impossible. Moreover the false data can lead to the wasting of expensive remedial chemistries when their addition was not needed. As a result a truly automated remedial chemical feed system is not feasible and a human operator is typically required to prevent the addition of remediating chemicals in the face of a “false alarm” thereby increasing operation costs.
Thus there is a clear need for and utility in an improved method of monitoring the conditions within a chemical plant. The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. §1.56(a) exists.